Base for electric lamps and similar articles



NOV. 17, 1931. R THQMAS 1,832,751

BASE FOR ELECTRIC LAMPS 'AND' SIMI-L AR ARTICLES Filed May 15, 1929 RALPH E. TJ-IDMASQ the sleeve. The base also comprises an Patented Nov. 17, 1931 UNITED STATES PATENT. OFFICE RALPH B. THOMAS, OI CLEVELAND, OHIO, ASSIGNOR To GENERAL ELECTRIC COMPANY,

A CORPORATIQN O F NEW YORK.

BABE FOR ELECTRIC LAMPS AND SIMILAR ARTICLES Application filed Kay 15,

' My invention relates to electric incandes-, cent lamps and other similar electric devices which comprise a bulb containing an electric energy translation element such as a filament and a base comprising terminals insulated from each other and connected to the leads of the energy translation, element. More particularly my invention relates to bases for such devices and to the means for attaching said bases to the bulb or other glass container. It has been the usual practice to attach the base by means of cement but there has been considerable trouble, especially in the case of the higher wattage lamps, on account of the crumbling or disintegra tion of the cement and the consequent loosening. of the base. Mechanically attached bases. which have the advantage of dispensing with cement, have been proposed heretof re but have not met with any degree of success. My invention has .for its object the provision of a mech nically attached cementless base which wil be not only extremely well attached but which will besimple to manufacture and apply. I

According to my invention, the base comprises a flexible and resilient attaching sleeve portion which fits on the end of the bulb neck and the contiguous surfaces of the bulb neck and sleeve are so shaped that when the sleeve is snapped into place there will be a resistance to withdrawal. thereof. One or more protuberances and depressions fitting together are preferably provided and it is preferred to have the depressions in the glass bulb neck and inner protuberances on the sleeve fitting into said depressions. Turning of the sleeve is also prevented by this construction. Three or more depressions and corresponding protuberances are preferred as prov ding a construction resistant to stresses in va ious planes tendingto disiodge uter s eeve portion which fits over the inner sleeve portion and is provided. for example. with the usual screw thread or is otherwise shaped to be received in a socket. Means are provided whereby the inner sleeve is caused to grip the bulb neck more tightly when the outer sleeve is placed over it. The preferred 1929. we no. man.

construction for accomplishin this is to screw thread the inner sleeve sot at the outer sleeve may be'screwed on to it. The zone of the inner sleeve in which are located the protuberances or depressions hereinbefore referred to is preferably weakened, as by slotting, so that the inner sleeve may be readily snapped into. place. A shoulder is'provided on the bulb neck and when the outer sleeve portion of the base has been screwed over the inner sleeve until its end engages thesaid shoulder, continued turning will cause the tages of my invention will appear fromthe following description of a specles thereof and from the-accompanying drawin s. In the drawings, Fig. 1 is an exploded elevational view of the parts of the base and a portion of the bulb; Fig. 2 is an elevation partially in vertical section of the base and the adjacent portion of the bulb neck; Fig. 3 is a horizontal section on the line 33 of Fig. 2; and Fig. 4 is an elevation partially broken away of a lamp provided with my form of base.

In the drawings, my invention is shown ap plied to an electric incandescent lamp comprising a bulb 10 having sealed therein a mount comprising the glass stem 11 supporting a ifilament 12. The ends of the filament are connected to inner leads 13 which are connected to the leading-in conductors 14. One of said conductors 14 is electrically connected to the shell 15 of the base and the other to the end contact 16 which is separated from the shell by insulation-17 according to well known practice. According to myinvention,

the end of the bulb neck is formed, as by molding during the sealing-in of the'stem, with aplurality of offset portions which are preferably depressions. It is preferred to have at least three of'said ofi'set portions and in the drawings four depressions 18 are shown. The base proper comprises an inner Sleeve 19 and Outer sleeve 20. The former is formed with ofi'set portions, specifically inner protuberances 21 of proper size and properly spaced so that they will register and be received in the depressions 18 of the bulb neck. The base is of sheet metal, such as brass, and the parts are shaped by stamping and spinning. To allow of ready application or removal and also to lend to theclamping action hereinafter described, the inner sleeve 19, at least for that zone thereof containing the protuberances 21, is resilient. As shown, this is accomplished by the removal of metal leaving the projections 22 which carry the proturberances. The remaining portion of the inner sleeve 19 is screw-threaded as a meansfor attachment to the outer sleeve 20. As a convenient means of attachment of one of the leading-in conductors 14, the upper flange 23 of the inner sleeve is provided with a projection 24 comprising a groove in which the end of the conductor is clamped or otherwise attached. The outer sleeve 20 is provided with the usual thread so that it may be screwed into a socket, and also so that the base parts may be assembled by screwing the outer sleeve 20 upon the inner sleeve 19. The bulb neck is provided with a shoulder 25 and the outer sleeve 20 is screwed down to engage that shoulder. Continuedscrewing down of the outer sleeve 20 causes the inner sleeve 19 to be drawn up further into the ou'ter'sleeve and there is a stretching and constriction of the lower portion of the inner' sleeve which causes a firmer clamping of the protuberances 21 in the depressions 18. The inner and outer sleeves of the base are then locked together. A convenient lock'is made by punching as with a chisel at one or more points which displaces inwardly projecting interlocked tongues 26 from the two sleeves. This has the advantage that there are no outward rojections to interfere with the insertion o the base in a socket. To assemble, the inner sleeve 19 is first forced over the end of the bulb neck in such manner that the protuberances 21 snap into the depressionslS. The .end of one of the leading-in conductors is then clamped or otherwise attached to the inner sleeve. The end of the other leading-in conductor is then threaded through the usual hole in the contact 16 of the outer sleeve 20 and-the said outer sleeve is then'screwed down on the inner sleeve causing its lower end to strike the shoulder 25 on the bulb neck after which a slight further turning will clamp the sleeve 19 firmly to the bulb neck. The outer and in ner base sleeves are then looked together by punching with a chisel to formthe interlocking inwardl rojecting tongues 26. 1

What I c mm as new and desire to secure by Letters Patent of the United States is 1. An electrical-device comprising a vitrefitting over the end of said neck, one or more inner sleeve to said neck.-

2. An electrical device comprising a vitreous container having a neck with a shoulder formed near the end thereof, an inner sleeve fitting over the end of said neck, one or more pairs of protuberances and depressions in the contiguous surfaces of said inner sleeve and neck fitting together and an outer sleeve, said sleeves having corresponding screw threads and said parts being so dimensioned that the screwing down of said outer sleeve against said shoulder causes a constriction of said inner sleeve in the zone of said protuberances or depressions to firmly clamp said inner sleeve to said neck, and said sleeves having inwardly extending punched out portions engaging eachother to lock said sleeves together. 3. An electrical device comprising a vitreous container having a neck with-a shoulder formed near the end thereof, an inner sleeve fitting over the end of said neck and comprismg a ring having integral projections therefrom with oflset portions therein, said neck having oflset portions corresponding to those of said inner sleeve, and an outer sleeve, said sleeves having corresponding screw threads and said parts being so dimensioned that the screwing down of said outer sleeve against said shoulder causes a. constriction of said inner sleeve in the zone of said offset portions to firmly clamp said inner sleeve to said neck.

4. An electrical device comprising a vitreous containenhaving a neck with a shoulder formed near the end thereof, an inner sleeve fitt ng over the end of said-neck and comprising a ring having integral projections therefrom with inward protuberances therein, said neck having depresssions corres 0ndmg to the protuberances in said inner s eeve, and an outer sleeve, said sleeves having corresponding screw threads and said parts being so dimensioned that the screwin down of said outer sleeve against said s oulder causes a constriction of said inner sleeve in the zone of said protuberances to firmly clamp said inner sleeve to said neck.

In witness whereof,'I have hereunto set my hand this 13th day of May, 1929.

RALPH B. THOMAS.

' ous container having a neck with a shoulder formed near the end thereof, an inner sleeve 

